To effectively utilize mobile communication network resources, the third generation mobile communication global standardization organization (3GPP) Release6 brings forward the MBMS of mobile communication networks, and thus a point-to-multipoint service of sending data from one data source to multiple users is provided in mobile communication networks, which can share network resource, improve the utilization of network resources, especially can share air interface resource.
FIG. 1 is a schematic view of the architecture of the radio network which supports broadcast multicast services. As shown in FIG. 1, in current 3GPP, the architecture of the radio network which supports broadcast multicast services comprises a broadcast multicast service server (BM-SC) 101 which is connected with a Gateway GPRS Support Node (GGSN) 102 via an interface Gmb or an interface Gi, wherein one BM-SC 101 can be connected with multiple GGSNs 102; the GGSN 102 is connected with a Serving GPRS Support Node (SGSN) 103 via an interface Gn/Gp, wherein one GGSN 102 can be connected with multiple SGSNs 103; the SGSN 103 is connected with a Universal Mobile Telecommunication System (UMTS) Terrestrial Radio Access Network (UTRAN) 104 via an interface Iu, and then the UTRAN 104 is connected with a user equipment (UE) 106 via an interface Uu, and the SGSN 103 can also be connected with a Global System for Mobile Communication System (GSM) Enhancement Radio Access Network (GERAN) 105 via interface Iu/Gb, and then it can be connected with a UE 107 via an interface Um. Wherein, the GGSN and the SGSN are nodes in the core network (CN) of radio networks.
It can be seen from the network architecture shown in FIG. 1 that in order to support the MBMS service, a mobile network functional entity, in particular a broadcast multicast service center, i.e. BM-SC, is added into the third generation mobile communication systems, the BM-SC is an entrance for content providers, which is used for authorizing and initiating a MBMS service and transmitting the MBMS content according to a predetermined time plan. In addition, MBMS-related functions are added into functional entities such as UE, UTRAN, GERAN, SGSN and GGSN.
The MBMS put forward in 3GPP can realize not only multicast and broadcast of message in plaintext at low rate, but also multicast and broadcast of multimedia services at high rate, which doubtlessly conforms to the development trend of mobile data in future. In order to further improve the transmission rate of the MBMS data, a solution of adopting dedicated independent carriers to bear the MBMS is currently put forward in 3GPP for Frequency Division Duplex (FDD) and 3.84 Mcps Time Division Duplex (TDD), that is, a frequency layer dedicated for transmitting the MBMS is individually established in the coverage area of current universal mobile communication systems, and the UE has the ability of receiving the MBMS transmitted through conventional carriers and dedicated carriers.
In 3GPP Release7 TR 25.905, a MBMS dedicated carrier mechanism suitable for WCDMA and HCR TDD systems is detailed, and the dedicated carrier can be the downlink carrier of WCDMA or HCR TDD carrier (all being downlink). To identify whether a carrier is a dedicated one, a system information block SIB3 in system information is proposed to be used for transmitting a MBSFN mark indicating whether the carrier is a dedicated carrier or not. If a carrier is dedicated for transmitting MBMS data services in a SFN mode, its specific information, such as the configuration of MBMS point-to-multipoint Control Channel (MCCH) and configuration of the scrambling code of MBMS point-to-multipoint Traffic Channel (MTCH), is carried in the system information block SIB5. Information carried in SIB3 and SIB5 substantially includes resources configuration states for MBMS data services transmission. The above solution also requires transmitting a dedicated carrier frequency list and an inter-Freq and intra-Freq measurement cell information list by SIB11. Except SIB3, SIB5 and SIB11, SIB information blocks currently transmitted in other conventional cells are not transmitted on MBMS dedicated carriers.
To simplify the MCCH signaling for the dedicated carriers, the dedicated carrier will not be directly used for uplink transmission, and MBMS access information will not be carried in the system information. Due to the MBMS signal transmitted for the dedicated carriers, when receiving data signals, the UE needs to take MBSFN multi-path signals in neighboring cells as conventional multi-path signals and perform physical layer-related process to it, and thus there is no need for the MCCH to transmit the RB information of neighboring cells for multi-path combining, i.e. MBMS neighboring cell P-T-M RB information.
Currently 3GPP does not propose a method for transmitting the MBMS at MBMS dedicated carriers in TDD systems.